Barangaroo was Australia’s first gasworks, in operation between 1839 and 1928 as Sydney’s electricity supply. Following decommissioning, the area was used as a commercial wharf built on reclaimed land using landfill. Consequently, the soil and groundwater on the site contained toxic contaminants, including arsenic, cadmium, chromium, copper, lead, mercury, nickel and zinc, ammonia, cyanide, total petroleum hydrocarbons, benzene, toluene, xylene, phenols, polychlorinated biphenyls, polyaromatic hydrocarbons, total recoverable hydrocarbons C6-C36 and Trichloroethene, in concentrations which were hazardous to human health and the environment. Synergy designed, constructed and operated a multi-barrier Water Treatment Plant to treat contaminated water and manage sludge associated with redevelopment of the contaminated Barangaroo site. Synergy’s technical objective was to dewater the site, de-contaminate the receiving waters (influent) and discharge treated water (effluent) direct into Sydney Harbour, in compliance with NSW EPA EPL 13336.
Synergy undertook all groundwater extraction, excavation dewatering, surface stormwater collection, water treatment, sludge dewatering, contaminant immobilisation, waste management and various remediation works on site for three years, playing a crucial role to enable the progression of this $8 billion project. Synergy’s treatment process addressed all 40 contaminants listed in the project’s EPL, treating more than 500 million litres of recovered water in a continuous process.